A burner for a gas turbine with a first fuel passage and a second fuel passage, which is encompassed in an essentially concentric manner by the first fuel passage, is disclosed for example in EP 1 277 920. The burner disclosed therein is designed to operate with a synthesis gas, the synthesis gas being split into a first sub-flow and a second sub-flow and the sub-flows being supplied to the burner separately through the first and second fuel passages. Regulation can be present for each sub-flow to supply the sub-flows in a regulated manner. In particular the sub-flows can be adjusted here as a function of the required power of the gas turbine. Regulation can in particular influence the gas mass flow or the respective specific calorific value of the fuel supplied. The calorific value is influenced by introducing natural gas to increase the calorific value or steam and/or nitrogen to reduce the calorific value.